Boss PSM-5 Power Supply & Master Switch Pedal (1984)

This pedal is in good condition with minor cosmetic wear. It has been fully tested and is 100% working well with no issues. The original box is not included.

This is the writeup on this pedal from the 1984 Boss pedal catalog

"The PSM-5 is a regulated power supply, capable of powering up to five 9v BOSS effects, (or other effects of a similar design). The PSM05 operates on AC power and comes with a PSA Series Adapter, which plugs into any conventional AC outlet ti give continuous operation without worry of battery run-down.

A parallel DC cord with 5 outlets comes with the PSM-5. This connects to the rear of the PSM-5 and to the AC Adapter jack on the rear of each BOSS compact pedal. 

But the PSM-5 is really much more than a conventional power supply, as it's also an effect loop selector at the same time. The Send jack on the left side of the PSM-5 connects to the input of the first effect in the chain. Then connect the output of the first effect to the input of the scond effect, and so on. The last effect in the chain connects back to the Return jack on the right side of the PSM-5.

The guitar (or other instrument) connects to the Guitar jack on the PSM-5, and the amp connects to the AMP jack. These connections yield two distinct loops, one running through the effect, and one going from guitar directly to the amp, bypassing the effects completely. A simple push of the footswitch selects one of the two loops. An LED indicator lights up when the effects loop is in operation.

The amazing PSM-5 powers your effects and controls them - all in one box"